llvm-6502/lib/Target/Sparc/SparcAsmPrinter.cpp
2004-03-06 05:30:21 +00:00

530 lines
18 KiB
C++

//===-- SparcV8AsmPrinter.cpp - SparcV8 LLVM assembly writer --------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains a printer that converts from our internal representation
// of machine-dependent LLVM code to GAS-format Sparc V8 assembly language.
//
//===----------------------------------------------------------------------===//
#include "SparcV8.h"
#include "SparcV8InstrInfo.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Module.h"
#include "llvm/Assembly/Writer.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Support/Mangler.h"
#include "Support/Statistic.h"
#include "Support/StringExtras.h"
#include "Support/CommandLine.h"
#include <cctype>
using namespace llvm;
namespace {
Statistic<> EmittedInsts("asm-printer", "Number of machine instrs printed");
struct V8Printer : public MachineFunctionPass {
/// Output stream on which we're printing assembly code.
///
std::ostream &O;
/// Target machine description which we query for reg. names, data
/// layout, etc.
///
TargetMachine &TM;
/// Name-mangler for global names.
///
Mangler *Mang;
V8Printer(std::ostream &o, TargetMachine &tm) : O(o), TM(tm) { }
/// We name each basic block in a Function with a unique number, so
/// that we can consistently refer to them later. This is cleared
/// at the beginning of each call to runOnMachineFunction().
///
typedef std::map<const Value *, unsigned> ValueMapTy;
ValueMapTy NumberForBB;
/// Cache of mangled name for current function. This is
/// recalculated at the beginning of each call to
/// runOnMachineFunction().
///
std::string CurrentFnName;
virtual const char *getPassName() const {
return "SparcV8 Assembly Printer";
}
void emitConstantValueOnly(const Constant *CV);
void emitGlobalConstant(const Constant *CV);
void printConstantPool(MachineConstantPool *MCP);
void printOperand(const MachineOperand &MI);
void printMachineInstruction(const MachineInstr *MI);
bool runOnMachineFunction(MachineFunction &F);
bool doInitialization(Module &M);
bool doFinalization(Module &M);
};
} // end of anonymous namespace
/// createSparcV8CodePrinterPass - Returns a pass that prints the SparcV8
/// assembly code for a MachineFunction to the given output stream,
/// using the given target machine description. This should work
/// regardless of whether the function is in SSA form.
///
FunctionPass *llvm::createSparcV8CodePrinterPass (std::ostream &o,
TargetMachine &tm) {
return new V8Printer(o, tm);
}
/// toOctal - Convert the low order bits of X into an octal digit.
///
static inline char toOctal(int X) {
return (X&7)+'0';
}
/// getAsCString - Return the specified array as a C compatible
/// string, only if the predicate isStringCompatible is true.
///
static void printAsCString(std::ostream &O, const ConstantArray *CVA) {
assert(CVA->isString() && "Array is not string compatible!");
O << "\"";
for (unsigned i = 0; i != CVA->getNumOperands(); ++i) {
unsigned char C = cast<ConstantInt>(CVA->getOperand(i))->getRawValue();
if (C == '"') {
O << "\\\"";
} else if (C == '\\') {
O << "\\\\";
} else if (isprint(C)) {
O << C;
} else {
switch(C) {
case '\b': O << "\\b"; break;
case '\f': O << "\\f"; break;
case '\n': O << "\\n"; break;
case '\r': O << "\\r"; break;
case '\t': O << "\\t"; break;
default:
O << '\\';
O << toOctal(C >> 6);
O << toOctal(C >> 3);
O << toOctal(C >> 0);
break;
}
}
}
O << "\"";
}
// Print out the specified constant, without a storage class. Only the
// constants valid in constant expressions can occur here.
void V8Printer::emitConstantValueOnly(const Constant *CV) {
if (CV->isNullValue())
O << "0";
else if (const ConstantBool *CB = dyn_cast<ConstantBool>(CV)) {
assert(CB == ConstantBool::True);
O << "1";
} else if (const ConstantSInt *CI = dyn_cast<ConstantSInt>(CV))
if (((CI->getValue() << 32) >> 32) == CI->getValue())
O << CI->getValue();
else
O << (unsigned long long)CI->getValue();
else if (const ConstantUInt *CI = dyn_cast<ConstantUInt>(CV))
O << CI->getValue();
else if (const ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(CV))
// This is a constant address for a global variable or function. Use the
// name of the variable or function as the address value.
O << Mang->getValueName(CPR->getValue());
else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
const TargetData &TD = TM.getTargetData();
switch(CE->getOpcode()) {
case Instruction::GetElementPtr: {
// generate a symbolic expression for the byte address
const Constant *ptrVal = CE->getOperand(0);
std::vector<Value*> idxVec(CE->op_begin()+1, CE->op_end());
if (unsigned Offset = TD.getIndexedOffset(ptrVal->getType(), idxVec)) {
O << "(";
emitConstantValueOnly(ptrVal);
O << ") + " << Offset;
} else {
emitConstantValueOnly(ptrVal);
}
break;
}
case Instruction::Cast: {
// Support only non-converting or widening casts for now, that is, ones
// that do not involve a change in value. This assertion is really gross,
// and may not even be a complete check.
Constant *Op = CE->getOperand(0);
const Type *OpTy = Op->getType(), *Ty = CE->getType();
// Pointers on ILP32 machines can be losslessly converted back and
// forth into 32-bit or wider integers, regardless of signedness.
assert(((isa<PointerType>(OpTy)
&& (Ty == Type::LongTy || Ty == Type::ULongTy
|| Ty == Type::IntTy || Ty == Type::UIntTy))
|| (isa<PointerType>(Ty)
&& (OpTy == Type::LongTy || OpTy == Type::ULongTy
|| OpTy == Type::IntTy || OpTy == Type::UIntTy))
|| (((TD.getTypeSize(Ty) >= TD.getTypeSize(OpTy))
&& OpTy->isLosslesslyConvertibleTo(Ty))))
&& "FIXME: Don't yet support this kind of constant cast expr");
O << "(";
emitConstantValueOnly(Op);
O << ")";
break;
}
case Instruction::Add:
O << "(";
emitConstantValueOnly(CE->getOperand(0));
O << ") + (";
emitConstantValueOnly(CE->getOperand(1));
O << ")";
break;
default:
assert(0 && "Unsupported operator!");
}
} else {
assert(0 && "Unknown constant value!");
}
}
// Print a constant value or values, with the appropriate storage class as a
// prefix.
void V8Printer::emitGlobalConstant(const Constant *CV) {
const TargetData &TD = TM.getTargetData();
if (CV->isNullValue()) {
O << "\t.zero\t " << TD.getTypeSize(CV->getType()) << "\n";
return;
} else if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) {
if (CVA->isString()) {
O << "\t.ascii\t";
printAsCString(O, CVA);
O << "\n";
} else { // Not a string. Print the values in successive locations
const std::vector<Use> &constValues = CVA->getValues();
for (unsigned i=0; i < constValues.size(); i++)
emitGlobalConstant(cast<Constant>(constValues[i].get()));
}
return;
} else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) {
// Print the fields in successive locations. Pad to align if needed!
const StructLayout *cvsLayout = TD.getStructLayout(CVS->getType());
const std::vector<Use>& constValues = CVS->getValues();
unsigned sizeSoFar = 0;
for (unsigned i=0, N = constValues.size(); i < N; i++) {
const Constant* field = cast<Constant>(constValues[i].get());
// Check if padding is needed and insert one or more 0s.
unsigned fieldSize = TD.getTypeSize(field->getType());
unsigned padSize = ((i == N-1? cvsLayout->StructSize
: cvsLayout->MemberOffsets[i+1])
- cvsLayout->MemberOffsets[i]) - fieldSize;
sizeSoFar += fieldSize + padSize;
// Now print the actual field value
emitGlobalConstant(field);
// Insert the field padding unless it's zero bytes...
if (padSize)
O << "\t.zero\t " << padSize << "\n";
}
assert(sizeSoFar == cvsLayout->StructSize &&
"Layout of constant struct may be incorrect!");
return;
} else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) {
// FP Constants are printed as integer constants to avoid losing
// precision...
double Val = CFP->getValue();
switch (CFP->getType()->getPrimitiveID()) {
default: assert(0 && "Unknown floating point type!");
case Type::FloatTyID: {
union FU { // Abide by C TBAA rules
float FVal;
unsigned UVal;
} U;
U.FVal = Val;
O << ".long\t" << U.UVal << "\t# float " << Val << "\n";
return;
}
case Type::DoubleTyID: {
union DU { // Abide by C TBAA rules
double FVal;
uint64_t UVal;
} U;
U.FVal = Val;
O << ".quad\t" << U.UVal << "\t# double " << Val << "\n";
return;
}
}
}
const Type *type = CV->getType();
O << "\t";
switch (type->getPrimitiveID()) {
case Type::BoolTyID: case Type::UByteTyID: case Type::SByteTyID:
O << ".byte";
break;
case Type::UShortTyID: case Type::ShortTyID:
O << ".word";
break;
case Type::FloatTyID: case Type::PointerTyID:
case Type::UIntTyID: case Type::IntTyID:
O << ".long";
break;
case Type::DoubleTyID:
case Type::ULongTyID: case Type::LongTyID:
O << ".quad";
break;
default:
assert (0 && "Can't handle printing this type of thing");
break;
}
O << "\t";
emitConstantValueOnly(CV);
O << "\n";
}
/// printConstantPool - Print to the current output stream assembly
/// representations of the constants in the constant pool MCP. This is
/// used to print out constants which have been "spilled to memory" by
/// the code generator.
///
void V8Printer::printConstantPool(MachineConstantPool *MCP) {
const std::vector<Constant*> &CP = MCP->getConstants();
const TargetData &TD = TM.getTargetData();
if (CP.empty()) return;
for (unsigned i = 0, e = CP.size(); i != e; ++i) {
O << "\t.section .rodata\n";
O << "\t.align " << (unsigned)TD.getTypeAlignment(CP[i]->getType())
<< "\n";
O << ".CPI" << CurrentFnName << "_" << i << ":\t\t\t\t\t#"
<< *CP[i] << "\n";
emitGlobalConstant(CP[i]);
}
}
/// runOnMachineFunction - This uses the printMachineInstruction()
/// method to print assembly for each instruction.
///
bool V8Printer::runOnMachineFunction(MachineFunction &MF) {
// BBNumber is used here so that a given Printer will never give two
// BBs the same name. (If you have a better way, please let me know!)
static unsigned BBNumber = 0;
O << "\n\n";
// What's my mangled name?
CurrentFnName = Mang->getValueName(MF.getFunction());
// Print out constants referenced by the function
printConstantPool(MF.getConstantPool());
// Print out labels for the function.
O << "\t.text\n";
O << "\t.align 16\n";
O << "\t.globl\t" << CurrentFnName << "\n";
O << "\t.type\t" << CurrentFnName << ", @function\n";
O << CurrentFnName << ":\n";
// Number each basic block so that we can consistently refer to them
// in PC-relative references.
NumberForBB.clear();
for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
I != E; ++I) {
NumberForBB[I->getBasicBlock()] = BBNumber++;
}
// Print out code for the function.
for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
I != E; ++I) {
// Print a label for the basic block.
O << ".LBB" << NumberForBB[I->getBasicBlock()] << ":\t# "
<< I->getBasicBlock()->getName() << "\n";
for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
II != E; ++II) {
// Print the assembly for the instruction.
O << "\t";
printMachineInstruction(II);
}
}
// We didn't modify anything.
return false;
}
std::string LowercaseString (const std::string &S) {
std::string result (S);
for (unsigned i = 0; i < S.length(); ++i)
if (isupper (result[i]))
result[i] = tolower(result[i]);
return result;
}
void V8Printer::printOperand(const MachineOperand &MO) {
const MRegisterInfo &RI = *TM.getRegisterInfo();
switch (MO.getType()) {
case MachineOperand::MO_VirtualRegister:
if (Value *V = MO.getVRegValueOrNull()) {
O << "<" << V->getName() << ">";
return;
}
// FALLTHROUGH
case MachineOperand::MO_MachineRegister:
if (MRegisterInfo::isPhysicalRegister(MO.getReg()))
O << "%" << LowercaseString (RI.get(MO.getReg()).Name);
else
O << "%reg" << MO.getReg();
return;
case MachineOperand::MO_SignExtendedImmed:
case MachineOperand::MO_UnextendedImmed:
O << (int)MO.getImmedValue();
return;
case MachineOperand::MO_PCRelativeDisp: {
ValueMapTy::const_iterator i = NumberForBB.find(MO.getVRegValue());
assert (i != NumberForBB.end()
&& "Could not find a BB in the NumberForBB map!");
O << ".LBB" << i->second << " # PC rel: " << MO.getVRegValue()->getName();
return;
}
case MachineOperand::MO_GlobalAddress:
O << Mang->getValueName(MO.getGlobal());
return;
case MachineOperand::MO_ExternalSymbol:
O << MO.getSymbolName();
return;
default:
O << "<unknown operand type>"; return;
}
}
/// printMachineInstruction -- Print out a single SparcV8 LLVM instruction
/// MI in GAS syntax to the current output stream.
///
void V8Printer::printMachineInstruction(const MachineInstr *MI) {
unsigned Opcode = MI->getOpcode();
const TargetInstrInfo &TII = TM.getInstrInfo();
const TargetInstrDescriptor &Desc = TII.get(Opcode);
O << Desc.Name << " ";
// print non-immediate, non-register-def operands
// then print immediate operands
// then print register-def operands.
std::vector<MachineOperand> print_order;
for (unsigned i = 0; i < MI->getNumOperands (); ++i)
if (!(MI->getOperand (i).isImmediate ()
|| (MI->getOperand (i).isRegister ()
&& MI->getOperand (i).isDef ())))
print_order.push_back (MI->getOperand (i));
for (unsigned i = 0; i < MI->getNumOperands (); ++i)
if (MI->getOperand (i).isImmediate ())
print_order.push_back (MI->getOperand (i));
for (unsigned i = 0; i < MI->getNumOperands (); ++i)
if (MI->getOperand (i).isRegister () && MI->getOperand (i).isDef ())
print_order.push_back (MI->getOperand (i));
for (unsigned i = 0, e = print_order.size (); i != e; ++i) {
printOperand (print_order[i]);
if (i != (print_order.size () - 1))
O << ", ";
}
O << "\n";
}
bool V8Printer::doInitialization(Module &M) {
Mang = new Mangler(M);
return false; // success
}
// SwitchSection - Switch to the specified section of the executable if we are
// not already in it!
//
static void SwitchSection(std::ostream &OS, std::string &CurSection,
const char *NewSection) {
if (CurSection != NewSection) {
CurSection = NewSection;
if (!CurSection.empty())
OS << "\t" << NewSection << "\n";
}
}
bool V8Printer::doFinalization(Module &M) {
const TargetData &TD = TM.getTargetData();
std::string CurSection;
// Print out module-level global variables here.
for (Module::const_giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
if (I->hasInitializer()) { // External global require no code
O << "\n\n";
std::string name = Mang->getValueName(I);
Constant *C = I->getInitializer();
unsigned Size = TD.getTypeSize(C->getType());
unsigned Align = TD.getTypeAlignment(C->getType());
if (C->isNullValue() &&
(I->hasLinkOnceLinkage() || I->hasInternalLinkage() ||
I->hasWeakLinkage() /* FIXME: Verify correct */)) {
SwitchSection(O, CurSection, ".data");
if (I->hasInternalLinkage())
O << "\t.local " << name << "\n";
O << "\t.comm " << name << "," << TD.getTypeSize(C->getType())
<< "," << (unsigned)TD.getTypeAlignment(C->getType());
O << "\t\t# ";
WriteAsOperand(O, I, true, true, &M);
O << "\n";
} else {
switch (I->getLinkage()) {
case GlobalValue::LinkOnceLinkage:
case GlobalValue::WeakLinkage: // FIXME: Verify correct for weak.
// Nonnull linkonce -> weak
O << "\t.weak " << name << "\n";
SwitchSection(O, CurSection, "");
O << "\t.section\t.llvm.linkonce.d." << name << ",\"aw\",@progbits\n";
break;
case GlobalValue::AppendingLinkage:
// FIXME: appending linkage variables should go into a section of
// their name or something. For now, just emit them as external.
case GlobalValue::ExternalLinkage:
// If external or appending, declare as a global symbol
O << "\t.globl " << name << "\n";
// FALL THROUGH
case GlobalValue::InternalLinkage:
if (C->isNullValue())
SwitchSection(O, CurSection, ".bss");
else
SwitchSection(O, CurSection, ".data");
break;
}
O << "\t.align " << Align << "\n";
O << "\t.type " << name << ",@object\n";
O << "\t.size " << name << "," << Size << "\n";
O << name << ":\t\t\t\t# ";
WriteAsOperand(O, I, true, true, &M);
O << " = ";
WriteAsOperand(O, C, false, false, &M);
O << "\n";
emitGlobalConstant(C);
}
}
delete Mang;
return false; // success
}